Medium concern

MSG

Monosodium glutamate · E621 · "flavor enhancer"

An industrially produced flavor enhancer derived from fermented starch or sugar. Most contemporary research has cleared MSG of the dramatic health claims it once carried — but it remains a useful marker for highly processed food.

Why we flag it

Let's be honest: MSG is one of the most studied food additives on earth, and the FDA, WHO, and European Food Safety Authority all classify it as generally safe. The historical "Chinese restaurant syndrome" panic was never substantiated by controlled trials, and the vast majority of people tolerate MSG without any reaction.

So why do we still flag it? Two reasons. First, a small subset of people do report headaches, flushing, or numbness from large doses on an empty stomach — the effect is real for them, even if rare. Second, and more importantly, MSG is almost exclusively used in heavily processed foods designed to be hyperpalatable. Flagging it isn't really about glutamate — it's about what the presence of MSG tells you about the rest of the product.

Where you'll find it

It's most common in savory processed foods, often hidden behind alternative names:

What to look for instead

If you want savory umami without the processed-food halo, plenty of whole-food sources deliver:

On packaged products, the clearest signal is "no MSG added" combined with a short, recognizable ingredient list. USDA Organic doesn't prohibit MSG explicitly, but it tends to exclude the heavily processed products where MSG appears.